The results of experimental studies of the influence of defect structure changes in a D16 polycrystalline aluminum alloy on its linear and nonlinear elastic properties are presented. The change of defect structure in the sample is caused by application of static cyclic stress (tension- compression - tension – compression) to it. Studies of the elastic properties of the test specimen during the application of variable loads were carried out using static, quasi-static and dynamic methods. Ultrasonic measurements were conducted using the pulse method. Investigation of nonlinear elastic properties of the test material were done using two methods: a dynamic spectral method according to the efficiency of generation of the second harmonic in the acoustic wavefield of finite amplitude at a frequency of 5 MHz and quasistatic method by measuring the change of velocity of acoustic waves in the sample as a function of the applied static pressure to it. Keywords: defects, nonclassic elastic nonlinearity, plastic deformation, spectral method, second harmonic.
M.V. Lomonosov Moscow State University, Faculty of Physics, Department of Acoustics Leninskie Gory 1-2, Moscow, Russia, 119991
Science News of the Faculty of Physics, Lomonosov Moscow State University
This new information publication, which is intended to convey to the staff, students and graduate students, faculty colleagues and partners of the main achievements of scientists and scientific information on the events in the life of university physicists.